feat: "try this" messages with support for interactivity (#10524)

This PR adds support for interactivity to the combined "try this"
messages that were introduced in #9966. In doing so, it moves the link
to apply a suggestion to a separate `[apply]` button in front of the
suggestion. Hints with diffs remain unchanged, as they did not
previously support interacting with terms in the diff, either.

<img width="379" height="256" alt="Suggestion with interactive message"
src="https://github.com/user-attachments/assets/7838ebf6-0613-46e7-bc88-468a05acbf51"
/>

src/Lean/Meta/Hint.lean

@@ -22,6 +22,103 @@ namespace Lean.Meta.Hint
 
 open Elab Tactic PrettyPrinter TryThis
 
+/--
+A widget for a clickable link (or icon) that inserts text into the document at a given position.
+
+The props to this widget are of the following form:
+```json
+{
+  "range": {
+    "start": {"line": 100, "character": 0},
+    "end":   {"line": 100, "character": 5}
+  },
+  "suggestion": "hi",
+  "acceptSuggestionProps": {
+    "kind": "text",
+    "hoverText": "Displayed on hover",
+    "linkText": "Displayed as the text of the link"
+  }
+}
+```
+... or the following form, where `codiconName` is one of the icons at
+https://microsoft.github.io/vscode-codicons/dist/codicon.html and `gaps` determines
+whether there are clickable spaces surrounding the icon:
+```json
+{
+  "range": {
+    "start": {"line": 100, "character": 0},
+    "end":   {"line": 100, "character": 5}
+  },
+  "suggestion": "hi",
+  "acceptSuggestionProps": {
+    "kind": "icon",
+    "hoverText": "Displayed on hover",
+    "codiconName": "search",
+    "gaps": true
+  }
+}
+```
+
+Note: we cannot add the `builtin_widget_module` attribute here because that would require importing
+`Lean.Widget.UserWidget`, which in turn imports much of `Lean.Elab` -- the module where we want to
+be able to use this widget. Instead, we register the attribute post-hoc when we declare the regular
+"Try This" widget in `Lean.Meta.Tactic.TryThis`.
+-/
+def textInsertionWidget : Widget.Module where
+  javascript := "
+import * as React from 'react';
+import { EditorContext, EnvPosContext } from '@leanprover/infoview';
+
+const e = React.createElement;
+export default function ({ range, suggestion, acceptSuggestionProps }) {
+  const pos = React.useContext(EnvPosContext)
+  const editorConnection = React.useContext(EditorContext)
+  function onClick() {
+    editorConnection.api.applyEdit({
+      changes: { [pos.uri]: [{ range, newText: suggestion }] }
+    })
+  }
+
+  if (acceptSuggestionProps.kind === 'text') {
+    return e('span', {
+        onClick,
+        title: acceptSuggestionProps.hoverText,
+        className: 'link pointer dim font-code',
+        style: { color: 'var(--vscode-textLink-foreground)' }
+      },
+      acceptSuggestionProps.linkText)
+  } else if (acceptSuggestionProps.kind === 'icon') {
+    if (acceptSuggestionProps.gaps) {
+      const icon = e('span', {
+        className: `codicon codicon-${acceptSuggestionProps.codiconName}`,
+        style: {
+          verticalAlign: 'sub',
+          fontSize: 'var(--vscode-editor-font-size)'
+        }
+      })
+      return e('span', {
+        onClick,
+        title: acceptSuggestionProps.hoverText,
+        className: `link pointer dim font-code`,
+        style: { color: 'var(--vscode-textLink-foreground)' }
+      }, ' ', icon, ' ')
+    } else {
+      return e('span', {
+        onClick,
+        title: acceptSuggestionProps.hoverText,
+        className: `link pointer dim font-code codicon codicon-${acceptSuggestionProps.codiconName}`,
+        style: {
+          color: 'var(--vscode-textLink-foreground)',
+          verticalAlign: 'sub',
+          fontSize: 'var(--vscode-editor-font-size)'
+        }
+      })
+    }
+
+  }
+  throw new Error('Unexpected `acceptSuggestionProps` kind: ' + acceptSuggestionProps.kind)
+}"
+
 /--
 A widget for rendering code action suggestions in error messages. Generally, this widget should not
 be used directly; instead, use `MessageData.hint`. Note that this widget is intended only for use
@@ -333,52 +430,82 @@ def mkSuggestionsMessage (suggestions : Array Suggestion) (ref : Syntax)
     (codeActionPrefix? : Option String) (forceList : Bool) : CoreM MessageData := do
   let mut msg := m!""
   for suggestion in suggestions do
-    if let some range := (suggestion.span?.getD ref).getRange? then
-      let { info, suggestions := suggestionArr, range := lspRange } ←
-        processSuggestions ref range #[suggestion.toTryThisSuggestion] codeActionPrefix?
-      pushInfoLeaf info
-      -- The following access is safe because
-      -- `suggestionsArr = #[suggestion.toTryThisSuggestion].map ...` (see `processSuggestions`)
-      let suggestionText := suggestionArr[0]!.2.1
-      let map ← getFileMap
-      let rangeContents := map.source.extract range.start range.stop
-      let edits ← do
-        if let some msgData := suggestion.messageData? then
-          pure #[(.insert, toString <| ← msgData.format)]
-        else
-          pure <| readableDiff rangeContents suggestionText suggestion.diffGranularity
-      let mut edits := edits
-      if let some previewRange := suggestion.previewSpan? >>= Syntax.getRange? then
-        if previewRange.includes range then
-          let map ← getFileMap
-          if previewRange.start < range.start then
-            edits := #[(.skip, (map.source.extract previewRange.start range.start))] ++ edits
-          if range.stop < previewRange.stop then
-            edits := edits.push (.skip, (map.source.extract range.stop previewRange.stop))
-      let diffJson := mkDiffJson edits
-      let json := json% {
-        diff: $diffJson,
-        suggestion: $suggestionText,
-        range: $lspRange
+    let some range := suggestion.span?.getD ref |>.getRange?
+      | continue
+    let edit ← suggestion.processEdit range
+    let suggestionText := edit.newText
+    let ref := Syntax.ofRange <| ref.getRange?.getD range
+    let codeActionTitleOverride? := suggestion.toCodeActionTitle?.map (· suggestionText)
+    let codeActionTitle := codeActionTitleOverride?.getD <| (codeActionPrefix?.getD "Try this: ") ++ suggestionText
+    let info := Info.ofCustomInfo {
+      stx := ref
+      value := Dynamic.mk {
+        edit
+        suggestion := suggestion.toTryThisSuggestion
+        codeActionTitle
+        : TryThisInfo
       }
-      let preInfo := suggestion.preInfo?.getD ""
-      let postInfo := suggestion.postInfo?.getD ""
-      let diffString :=
-        if suggestion.diffGranularity matches .none then
-          edits.foldl (· ++ ·.2) ""
-        else
-          mkDiffString edits
-      let widget := MessageData.ofWidget {
-          id := ``tryThisDiffWidget
-          javascriptHash := tryThisDiffWidget.javascriptHash
-          props := return json
-        } diffString
-      let widgetMsg := m!"{preInfo}{widget}{postInfo}"
-      let suggestionMsg := if suggestions.size == 1 && !forceList then
-        m!"\n{widgetMsg}"
+    }
+    pushInfoLeaf info
+    let map ← getFileMap
+    let rangeContents := map.source.extract range.start range.stop
+    let edits ← do
+      if let some msgData := suggestion.messageData? then
+        pure #[(.insert, toString <| ← msgData.format)]
       else
-        m!"\n" ++ MessageData.nest 2 m!"• {widgetMsg}"
-      msg := msg ++ MessageData.nestD suggestionMsg
+        pure <| readableDiff rangeContents suggestionText suggestion.diffGranularity
+    let mut edits := edits
+    if let some previewRange := suggestion.previewSpan? >>= Syntax.getRange? then
+      if previewRange.includes range then
+        let map ← getFileMap
+        if previewRange.start < range.start then
+          edits := #[(.skip, (map.source.extract previewRange.start range.start))] ++ edits
+        if range.stop < previewRange.stop then
+          edits := edits.push (.skip, (map.source.extract range.stop previewRange.stop))
+    let preInfo := suggestion.preInfo?.getD ""
+    let postInfo := suggestion.postInfo?.getD ""
+    let isDiffSuggestion :=
+      ! (suggestion.diffGranularity matches .none) && suggestion.messageData?.isNone
+        || suggestion.previewSpan?.isSome
+    let suggestionMsg :=
+      if ! isDiffSuggestion then
+        let applyButton := MessageData.ofWidget {
+          id := ``textInsertionWidget
+          javascriptHash := textInsertionWidget.javascriptHash
+          props := return json% {
+            range: $edit.range,
+            suggestion: $suggestionText,
+            acceptSuggestionProps: {
+              kind: "text",
+              hoverText: "Apply suggestion",
+              linkText: "[apply]"
+            }
+          }
+        } "[apply]"
+        m!"\n{applyButton} {preInfo}{toMessageData suggestion}{postInfo}"
+      else
+        let diffJson := mkDiffJson edits
+        let json := json% {
+          diff: $diffJson,
+          suggestion: $suggestionText,
+          range: $edit.range
+        }
+        let diffString :=
+          if suggestion.diffGranularity matches .none then
+            edits.foldl (· ++ ·.2) ""
+          else
+            mkDiffString edits
+        let diffWidget := MessageData.ofWidget {
+            id := ``tryThisDiffWidget
+            javascriptHash := tryThisDiffWidget.javascriptHash
+            props := return json
+          } diffString
+        let msg := m!"{preInfo}{diffWidget}{postInfo}"
+        if suggestions.size == 1 && !forceList then
+          m!"\n{msg}"
+        else
+          m!"\n" ++ MessageData.nest 2 m!"• {msg}"
+    msg := msg ++ MessageData.nestD suggestionMsg
   return msg
 
 /--

src/Lean/Meta/Tactic/TryThis.lean

@@ -34,6 +34,7 @@ open Lean Elab Tactic PrettyPrinter Meta Server RequestM
 
 -- Because we can't use `builtin_widget_module` in `Lean.Meta.Hint`, we add the attribute here
 attribute [builtin_widget_module] Hint.tryThisDiffWidget
+attribute [builtin_widget_module] Hint.textInsertionWidget
 
 /-! # Code action -/
 
@@ -45,24 +46,17 @@ apply the replacement.
   let doc ← readDoc
   pure <| snap.infoTree.foldInfo (init := #[]) fun _ctx info result => Id.run do
     let .ofCustomInfo { stx, value } := info | result
-    let some { range, suggestionTexts, codeActionPrefix? } :=
+    let some { edit, codeActionTitle, .. } :=
       value.get? TryThisInfo | result
     let some stxRange := stx.getRange? | result
     let stxRange := doc.meta.text.utf8RangeToLspRange stxRange
     unless stxRange.start.line ≤ params.range.end.line do return result
     unless params.range.start.line ≤ stxRange.end.line do return result
-    let mut result := result
-    for h : i in *...suggestionTexts.size do
-      let (newText, title?) := suggestionTexts[i]
-      let title := title?.getD <| (codeActionPrefix?.getD "Try this: ") ++ newText
-      result := result.push {
-        eager.title := title
-        eager.kind? := "quickfix"
-        -- Only make the first option preferred
-        eager.isPreferred? := if i = 0 then true else none
-        eager.edit? := some <| .ofTextEdit doc.versionedIdentifier { range, newText }
-      }
-    result
+    result.push {
+      eager.title := codeActionTitle
+      eager.kind? := "quickfix"
+      eager.edit? := some <| .ofTextEdit doc.versionedIdentifier edit
+    }
 
 /-! # Formatting -/
 
@@ -72,7 +66,7 @@ def delabToRefinableSyntax (e : Expr) : MetaM Term :=
 
 /-- Delaborate `e` into a suggestion suitable for use by `refine`. -/
 def delabToRefinableSuggestion (e : Expr) : MetaM Suggestion :=
-  return { suggestion := ← delabToRefinableSyntax e }
+  return { suggestion := ← delabToRefinableSyntax e, messageData? := ← addMessageContext <| toMessageData e }
 
 /-- Add a "try this" suggestion. This has two effects:
 
@@ -187,19 +181,19 @@ Remark: We cannot determine if a tactic requires `expose_names` merely by inspec
 (shadowed variables are delaborated without daggers) nor the underlying `Expr` used to produce it
 (some inaccessible names may be implicit arguments that do not appear in the delaborated syntax).
 -/
-private def mkValidatedTactic (tac : TSyntax `tactic)
+private def mkValidatedTactic (tac : TSyntax `tactic) (msg : MessageData)
     (initialState : Tactic.SavedState) (expectedType? : Option Expr := none) :
-    TacticM (Option (TSyntax `tactic)) := do
+    TacticM (Option (TSyntax `tactic × MessageData)) := do
   try
     evalTacticWithState initialState tac expectedType?
-    return some tac
+    return some (tac, msg)
   catch _ =>
     -- Note: we must use `(expose_names; _)` and not `· expose_names; _` to avoid generating
     -- spurious tactic-abort exceptions, since these tactics may not close the goal
     let tac ← `(tactic| (expose_names; $tac))
     try
       evalTacticWithState initialState tac expectedType?
-      return some tac
+      return some (tac, m!"(expose_names; {msg})")
     catch _ =>
       return none
 
@@ -231,7 +225,7 @@ private def addExactSuggestionCore (addSubgoalsMsg : Bool) (checkState? : Option
   let hasMVars := !mvars.isEmpty
   let (suggestion, messageData) ← mkExactSuggestionSyntax e (useRefine := hasMVars)
   let some checkState := checkState? | return .inl suggestion
-  let some suggestion ← mkValidatedTactic suggestion checkState
+  let some (suggestion, messageData) ← mkValidatedTactic suggestion messageData checkState
     | let messageData := m!"(expose_names; {messageData})"
       return .inr <| mkFailedToMakeTacticMsg m!"a {if hasMVars then "partial " else ""}proof" messageData
   let postInfo? ← if !addSubgoalsMsg || mvars.isEmpty then pure none else
@@ -241,7 +235,7 @@ private def addExactSuggestionCore (addSubgoalsMsg : Bool) (checkState? : Option
       let e ← withExposedNames <| PrettyPrinter.ppExpr (← instantiateMVars (← g.getType))
       str := str ++ Format.pretty ("\n-- ⊢ " ++ e)
     pure str
-  return .inl { suggestion := suggestion, postInfo? }
+  return .inl { suggestion := suggestion, postInfo?, messageData? := messageData }
 
 /-- Add an `exact e` or `refine e` suggestion.
 
@@ -374,11 +368,12 @@ def addHaveSuggestion (ref : Syntax) (h? : Option Name) (t? : Option Expr) (e :
         pure (← `(tactic| let $(mkIdent h):ident := $estx), m!"let {h} := {e}")
     pure (tac, ← addMessageContext msg)
   if let some checkState := checkState? then
-    let some tac' ← mkValidatedTactic tac checkState
+    let some (tac', msg') ← mkValidatedTactic tac msg checkState
       | logInfo <| mkFailedToMakeTacticMsg "a proof" msg
         return
     tac := tac'
-  addSuggestion ref (s := { suggestion := tac }) origSpan?
+    msg := msg'
+  addSuggestion ref (s := { suggestion := tac, messageData? := msg }) origSpan?
 
 open Lean.Parser.Tactic
 open Lean.Syntax
@@ -400,7 +395,7 @@ def addRewriteSuggestion (ref : Syntax) (rules : List (Expr × Bool))
   (type? : LOption Expr := .undef) (loc? : Option Expr := none)
   (origSpan? : Option Syntax := none) (checkState? : Option Tactic.SavedState := none) :
     TacticM Unit := do
-  let mut (tac, tacMsg, extraMsg, extraStr) ← withExposedNames do
+  let mut (tac, tacMsg, extraMsg) ← withExposedNames do
     let rulesStx := TSepArray.ofElems <| ← rules.toArray.mapM fun ⟨e, symm⟩ => do
       let t ← delabToRefinableSyntax e
       if symm then `(rwRule| ← $t:term) else `(rwRule| $t:term)
@@ -423,22 +418,23 @@ def addRewriteSuggestion (ref : Syntax) (rules : List (Expr × Bool))
       else
         m!"rw {rulesMsg}"
 
-    let (extraMsg, extraStr) ←
+    let extraMsg ←
       match type? with
       | .some type =>
-        pure (← addMessageContext m!"\n-- {type}", s!"\n-- {← PrettyPrinter.ppExpr type}")
-      | .none => pure (m!"\n-- no goals", "\n-- no goals")
-      | .undef => pure (m!"", "")
-    return (tac, tacMsg, extraMsg, extraStr)
+        pure <| ← addMessageContext m!"\n-- {type}"
+      | .none => pure m!"\n-- no goals"
+      | .undef => pure m!""
+    return (tac, tacMsg, extraMsg)
 
   if let some checkState := checkState? then
     let type? := match type? with
       | .some type => some type
       | _ => none
-    let some tac' ← mkValidatedTactic tac checkState type?
+    let some (tac', tacMsg') ← mkValidatedTactic tac tacMsg checkState type?
       | tacMsg := m!"(expose_names; {tacMsg})"
         logInfo <| mkFailedToMakeTacticMsg "an applicable rewrite lemma" (tacMsg ++ extraMsg)
         return
     tac := tac'
-  addSuggestion ref (s := { suggestion := tac, postInfo? := extraStr })
+    tacMsg := tacMsg'
+  addSuggestion ref (s := { suggestion := tac, messageData? := tacMsg ++ extraMsg })
     origSpan?

src/Lean/Meta/TryThis.lean

@@ -28,21 +28,6 @@ open PrettyPrinter
 
 /-! # Code action information -/
 
-/-- A packet of information about a "Try this" suggestion
-that we store in the infotree for the associated code action to retrieve. -/
-structure TryThisInfo : Type where
-  /-- The textual range to be replaced by one of the suggestions. -/
-  range : Lsp.Range
-  /--
-  A list of suggestions for the user to choose from.
-  Each suggestion may optionally come with an override for the code action title.
-  -/
-  suggestionTexts : Array (String × Option String)
-  /-- The prefix to display before the code action for a "Try this" suggestion if no custom code
-  action title is provided. If not provided, `"Try this: "` is used. -/
-  codeActionPrefix? : Option String
-  deriving TypeName
-
 /-! # `Suggestion` data -/
 
 -- TODO: we could also support `Syntax` and `Format`
@@ -175,11 +160,28 @@ attribute [deprecated "The `style?` property is not used anymore." (since := "20
 
 /- Use `toMessageData` of the suggestion text. -/
 instance : ToMessageData Suggestion where
-  toMessageData s := toMessageData s.suggestion
+  toMessageData s := s.messageData?.getD (toMessageData s.suggestion)
 
 instance : Coe SuggestionText Suggestion where
   coe t := { suggestion := t }
 
+/--
+A packet of information about a "Try this" suggestion
+that we store in the infotree for the associated code action to retrieve.
+-/
+structure TryThisInfo : Type where
+  /-- Suggestion edit as it will be applied to the editor document. -/
+  edit : Lsp.TextEdit
+  /-- Title of the code action that is displayed in the code action selection dialog. -/
+  codeActionTitle : String
+  /--
+  Original suggestion that this `TryThisInfo` was derived from.
+  Stored so that meta-code downstream can extract the suggestions
+  produced by a tactic from the `InfoTree`.
+  -/
+  suggestion : Suggestion
+  deriving TypeName
+
 /-! # Formatting -/
 
 /-- Yields `(indent, column)` given a `FileMap` and a `String.Range`, where `indent` is the number
@@ -226,54 +228,16 @@ def prettyExtra (s : SuggestionText) (w : Option Nat := none)
 
 end SuggestionText
 
-/-- Converts a `Suggestion` to `Json` in `CoreM`. We need `CoreM` in order to pretty-print syntax.
+def Suggestion.pretty (s : Suggestion) (w : Option Nat := none) (indent column : Nat := 0) :
+    CoreM String := do
+  s.suggestion.prettyExtra w indent column
 
-This also returns a `String × Option String` consisting of the pretty-printed text and any custom
-code action title if `toCodeActionTitle?` is provided.
-
-If `w := none`, then `w := getInputWidth (← getOptions)` is used.
--/
-def Suggestion.toJsonAndInfoM (s : Suggestion) (w : Option Nat := none) (indent column : Nat := 0) :
-    CoreM (Json × String × Option String) := do
-  let text ← s.suggestion.prettyExtra w indent column
-  let mut json := [("suggestion", (text : Json))]
-  if let some preInfo := s.preInfo? then json := ("preInfo", preInfo) :: json
-  if let some postInfo := s.postInfo? then json := ("postInfo", postInfo) :: json
-  return (Json.mkObj json, text, s.toCodeActionTitle?.map (· text))
-
-/--
-Represents processed data for a collection of suggestions that can be passed to a widget and pushed
-in an info leaf.
-
-It contains the following data:
-* `suggestions`: tuples of the form `(j, t, p)` where `j` is JSON containing a suggestion and its
-  pre- and post-info, `t` is the text to be inserted by the suggestion, and `p` is the code action
-  prefix thereof.
-* `info`: the `TryThisInfo` data corresponding to a collection of suggestions
-* `range`: the range at which the suggestion is to be applied.
--/
-structure ProcessedSuggestions where
-  suggestions : Array (Json × String × Option String)
-  info : Elab.Info
-  range : Lsp.Range
-
-/--
-Processes an array of `Suggestion`s into data that can be used to construct a code-action info leaf
-and "try this" widget.
--/
-def processSuggestions (ref : Syntax) (range : String.Range) (suggestions : Array Suggestion)
-    (codeActionPrefix? : Option String) : CoreM ProcessedSuggestions := do
+def Suggestion.processEdit (s : Suggestion) (range : String.Range) : CoreM Lsp.TextEdit := do
   let map ← getFileMap
   -- FIXME: this produces incorrect results when `by` is at the beginning of the line, i.e.
   -- replacing `tac` in `by tac`, because the next line will only be 2 space indented
   -- (less than `tac` which starts at column 3)
   let (indent, column) := getIndentAndColumn map range
-  let suggestions ← suggestions.mapM (·.toJsonAndInfoM (indent := indent) (column := column))
-  let suggestionTexts := suggestions.map (·.2)
-  let ref := Syntax.ofRange <| ref.getRange?.getD range
+  let newText ← s.pretty (indent := indent) (column := column)
   let range := map.utf8RangeToLspRange range
-  let info := .ofCustomInfo {
-    stx := ref
-    value := Dynamic.mk { range, suggestionTexts, codeActionPrefix? : TryThisInfo }
-  }
-  return { info, suggestions, range }
+  return { range, newText }

tests/lean/4591.lean.expected.out

@@ -1,2 +1,2 @@
 Try this:
-  simp only [Nat.foo]
+  [apply] simp only [Nat.foo]

tests/lean/interactive/builtinCodeactions.lean.expected.out

@@ -5,7 +5,6 @@
 [{"title":
   "Try this: simp only [AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA,\n    aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa] at h",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument": {"version": 1, "uri": "file:///builtinCodeactions.lean"},

tests/lean/interactive/structInstFieldHints.lean.expected.out

@@ -4,7 +4,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Add missing fields",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument": {"version": 1, "uri": "file:///structInstFieldHints.lean"},
@@ -20,7 +19,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Add missing fields",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument": {"version": 1, "uri": "file:///structInstFieldHints.lean"},
@@ -36,7 +34,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Add missing fields",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument": {"version": 1, "uri": "file:///structInstFieldHints.lean"},
@@ -52,7 +49,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Add missing fields",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument": {"version": 1, "uri": "file:///structInstFieldHints.lean"},
@@ -68,7 +64,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Add missing fields",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument": {"version": 1, "uri": "file:///structInstFieldHints.lean"},
@@ -84,7 +79,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Add missing fields",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument": {"version": 1, "uri": "file:///structInstFieldHints.lean"},
@@ -100,7 +94,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Add missing fields",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument": {"version": 1, "uri": "file:///structInstFieldHints.lean"},
@@ -116,7 +109,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Add missing fields",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument": {"version": 1, "uri": "file:///structInstFieldHints.lean"},
@@ -132,7 +124,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Add missing fields",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument": {"version": 1, "uri": "file:///structInstFieldHints.lean"},
@@ -148,7 +139,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Add missing fields",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument": {"version": 1, "uri": "file:///structInstFieldHints.lean"},
@@ -163,7 +153,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Add missing fields",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument": {"version": 1, "uri": "file:///structInstFieldHints.lean"},
@@ -178,7 +167,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Add missing fields",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument": {"version": 1, "uri": "file:///structInstFieldHints.lean"},
@@ -193,7 +181,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Add missing fields",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument": {"version": 1, "uri": "file:///structInstFieldHints.lean"},
@@ -208,7 +195,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Add missing fields",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument": {"version": 1, "uri": "file:///structInstFieldHints.lean"},
@@ -224,7 +210,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Add missing fields",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument": {"version": 1, "uri": "file:///structInstFieldHints.lean"},
@@ -239,7 +224,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Add missing fields",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument": {"version": 1, "uri": "file:///structInstFieldHints.lean"},
@@ -254,7 +238,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Add missing fields",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument": {"version": 1, "uri": "file:///structInstFieldHints.lean"},
@@ -270,7 +253,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Add missing fields",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument": {"version": 1, "uri": "file:///structInstFieldHints.lean"},
@@ -287,7 +269,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Add missing fields",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument": {"version": 1, "uri": "file:///structInstFieldHints.lean"},
@@ -303,7 +284,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Add missing fields",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument": {"version": 1, "uri": "file:///structInstFieldHints.lean"},
@@ -319,7 +299,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Add missing fields",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument": {"version": 1, "uri": "file:///structInstFieldHints.lean"},
@@ -335,7 +314,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Add missing fields",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument": {"version": 1, "uri": "file:///structInstFieldHints.lean"},
@@ -351,7 +329,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Add missing fields",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument": {"version": 1, "uri": "file:///structInstFieldHints.lean"},
@@ -366,7 +343,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Add missing fields",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument": {"version": 1, "uri": "file:///structInstFieldHints.lean"},
@@ -383,7 +359,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Add missing fields",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument": {"version": 1, "uri": "file:///structInstFieldHints.lean"},
@@ -399,7 +374,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Add missing fields",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument": {"version": 1, "uri": "file:///structInstFieldHints.lean"},
@@ -415,7 +389,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Add missing fields",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument": {"version": 1, "uri": "file:///structInstFieldHints.lean"},
@@ -432,7 +405,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Add missing fields",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument": {"version": 1, "uri": "file:///structInstFieldHints.lean"},
@@ -449,7 +421,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Add missing fields",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument": {"version": 1, "uri": "file:///structInstFieldHints.lean"},
@@ -466,7 +437,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Add missing fields",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument": {"version": 1, "uri": "file:///structInstFieldHints.lean"},
@@ -482,7 +452,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Add missing fields",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument": {"version": 1, "uri": "file:///structInstFieldHints.lean"},
@@ -498,7 +467,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Add missing fields",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument": {"version": 1, "uri": "file:///structInstFieldHints.lean"},
@@ -515,7 +483,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Add missing fields",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument": {"version": 1, "uri": "file:///structInstFieldHints.lean"},
@@ -532,7 +499,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Add missing fields",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument": {"version": 1, "uri": "file:///structInstFieldHints.lean"},
@@ -548,7 +514,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Add missing fields",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument": {"version": 1, "uri": "file:///structInstFieldHints.lean"},
@@ -564,7 +529,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Add missing fields",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument": {"version": 1, "uri": "file:///structInstFieldHints.lean"},

tests/lean/interactive/terminationBySuggestion.lean.expected.out

@@ -4,7 +4,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Try this: termination_by (n, m)",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument":
@@ -20,7 +19,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Try this: termination_by structural n",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument":
@@ -36,7 +34,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Try this: termination_by structural x => x",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument":
@@ -52,7 +49,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Try this: termination_by n",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument":
@@ -68,7 +64,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Try this: termination_by x1 => x1",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument":

tests/lean/interactive/tryThisCodeAction.lean.expected.out

@@ -4,7 +4,6 @@
  "context": {"diagnostics": []}}
 [{"title": "Try this: simp only",
   "kind": "quickfix",
-  "isPreferred": true,
   "edit":
   {"documentChanges":
    [{"textDocument": {"version": 1, "uri": "file:///tryThisCodeAction.lean"},

tests/lean/librarySearch.lean

@@ -21,14 +21,14 @@ noncomputable section
 
 /--
 info: Try this:
-  exact Nat.lt_add_one x
+  [apply] exact Nat.lt_add_one x
 -/
 #guard_msgs in
 example (x : Nat) : x ≠ x.succ := Nat.ne_of_lt (by apply?)
 
 /--
 info: Try this:
-  exact Nat.zero_lt_succ 1
+  [apply] exact Nat.zero_lt_succ 1
 -/
 #guard_msgs in
 example : 0 ≠ 1 + 1 := Nat.ne_of_lt (by apply?)
@@ -37,28 +37,28 @@ example : 0 ≠ 1 + 1 := Nat.ne_of_lt (by exact Fin.pos')
 
 /--
 info: Try this:
-  exact Nat.add_comm x y
+  [apply] exact Nat.add_comm x y
 -/
 #guard_msgs in
 example (x y : Nat) : x + y = y + x := by apply?
 
 /--
 info: Try this:
-  exact fun a => Nat.add_le_add_right a k
+  [apply] exact fun a => Nat.add_le_add_right a k
 -/
 #guard_msgs in
 example (n m k : Nat) : n ≤ m → n + k ≤ m + k := by apply?
 
 /--
 info: Try this:
-  exact Nat.mul_dvd_mul_left a w
+  [apply] exact Nat.mul_dvd_mul_left a w
 -/
 #guard_msgs in
 example (_ha : a > 0) (w : b ∣ c) : a * b ∣ a * c := by apply?
 
 /--
 info: Try this:
-  Nat.lt_add_one x
+  [apply] Nat.lt_add_one x
 -/
 #guard_msgs in
 example : x < x + 1 := exact?%
@@ -73,19 +73,19 @@ example (x y : Nat) : x ≤ y := exact?%
 
 /--
 info: Try this:
-  exact p
+  [apply] exact p
 -/
 #guard_msgs in
 example (P : Prop) (p : P) : P := by apply?
 /--
 info: Try this:
-  exact False.elim (np p)
+  [apply] exact False.elim (np p)
 -/
 #guard_msgs in
 example (P : Prop) (p : P) (np : ¬P) : false := by apply?
 /--
 info: Try this:
-  exact h x rfl
+  [apply] exact h x rfl
 -/
 #guard_msgs in
 example (X : Type) (P : Prop) (x : X) (h : ∀ x : X, x = x → P) : P := by apply?
@@ -101,7 +101,7 @@ example (α : Prop) : α → α := by apply?
 
 /--
 info: Try this:
-  exact Nat.add_comm a b
+  [apply] exact Nat.add_comm a b
 -/
 #guard_msgs in
 example (a b : Nat) : a + b = b + a :=
@@ -109,7 +109,7 @@ by apply?
 
 /--
 info: Try this:
-  exact Nat.mul_sub_left_distrib n m k
+  [apply] exact Nat.mul_sub_left_distrib n m k
 -/
 #guard_msgs in
 example (n m k : Nat) : n * (m - k) = n * m - n * k :=
@@ -119,7 +119,7 @@ attribute [symm] Eq.symm
 
 /--
 info: Try this:
-  exact Eq.symm (Nat.mul_sub_left_distrib n m k)
+  [apply] exact Eq.symm (Nat.mul_sub_left_distrib n m k)
 -/
 #guard_msgs in
 example (n m k : Nat) : n * m - n * k = n * (m - k) := by
@@ -127,21 +127,21 @@ example (n m k : Nat) : n * m - n * k = n * (m - k) := by
 
 /--
 info: Try this:
-  exact eq_comm
+  [apply] exact eq_comm
 -/
 #guard_msgs in
 example {α : Type} (x y : α) : x = y ↔ y = x := by apply?
 
 /--
 info: Try this:
-  exact Nat.add_pos_right a hb
+  [apply] exact Nat.add_pos_right a hb
 -/
 #guard_msgs in
 example (a b : Nat) (_ha : 0 < a) (hb : 0 < b) : 0 < a + b := by apply?
 
 /--
 info: Try this:
-  exact Nat.add_pos_right a hb
+  [apply] exact Nat.add_pos_right a hb
 -/
 #guard_msgs in
 -- Verify that if maxHeartbeats is 0 we don't stop immediately.
@@ -152,14 +152,14 @@ section synonym
 
 /--
 info: Try this:
-  exact Nat.add_pos_right a hb
+  [apply] exact Nat.add_pos_right a hb
 -/
 #guard_msgs in
 example (a b : Nat) (_ha : a > 0) (hb : 0 < b) : 0 < a + b := by apply?
 
 /--
 info: Try this:
-  exact Nat.le_of_dvd w h
+  [apply] exact Nat.le_of_dvd w h
 -/
 #guard_msgs in
 example (a b : Nat) (h : a ∣ b) (w : b > 0) : a ≤ b :=
@@ -167,7 +167,7 @@ by apply?
 
 /--
 info: Try this:
-  exact Nat.le_of_dvd w h
+  [apply] exact Nat.le_of_dvd w h
 -/
 #guard_msgs in
 example (a b : Nat) (h : a ∣ b) (w : b > 0) : b ≥ a := by apply?
@@ -175,13 +175,13 @@ example (a b : Nat) (h : a ∣ b) (w : b > 0) : b ≥ a := by apply?
 -- TODO: A lemma with head symbol `¬` can be used to prove `¬ p` or `⊥`
 /--
 info: Try this:
-  exact Nat.not_lt_zero a
+  [apply] exact Nat.not_lt_zero a
 -/
 #guard_msgs in
 example (a : Nat) : ¬ (a < 0) := by apply?
 /--
 info: Try this:
-  exact Nat.not_succ_le_zero a h
+  [apply] exact Nat.not_succ_le_zero a h
 -/
 #guard_msgs in
 example (a : Nat) (h : a < 0) : False := by apply?
@@ -200,20 +200,20 @@ theorem lemma_with_false_in_head (a b : Nat) (_h1 : a < b) (h2 : P a) : False :=
 
 /--
 info: Try this:
-  exact lemma_with_gt_in_head a h
+  [apply] exact lemma_with_gt_in_head a h
 -/
 #guard_msgs in
 example (a : Nat) (h : P a) : 0 > a := by apply?
 /--
 info: Try this:
-  exact lemma_with_gt_in_head a h
+  [apply] exact lemma_with_gt_in_head a h
 -/
 #guard_msgs in
 example (a : Nat) (h : P a) : a < 0 := by apply?
 
 /--
 info: Try this:
-  exact lemma_with_false_in_head a b h1 h2
+  [apply] exact lemma_with_false_in_head a b h1 h2
 -/
 #guard_msgs in
 example (a b : Nat) (h1 : a < b) (h2 : P a) : False := by apply?
@@ -225,7 +225,7 @@ end synonym
 
 /--
 info: Try this:
-  exact fun P => iff_not_self
+  [apply] exact fun P => iff_not_self
 -/
 #guard_msgs in
 example : ∀ P : Prop, ¬(P ↔ ¬P) := by apply?
@@ -241,22 +241,21 @@ theorem p_iff_q (i : Nat) : P i ↔ Q i :=
 
 /--
 info: Try this:
-  exact (p_iff_q a).mp h
+  [apply] exact (p_iff_q a).mp h
 -/
 #guard_msgs in
 example {a : Nat} (h : P a) : Q a := by apply?
 
 /--
 info: Try this:
-  exact (p_iff_q a).mpr h
+  [apply] exact (p_iff_q a).mpr h
 -/
 #guard_msgs in
 example {a : Nat} (h : Q a) : P a := by apply?
 
 /--
 info: Try this:
-  exact
-    (Nat.dvd_add_iff_left h₁).mpr h₂
+  [apply] exact (Nat.dvd_add_iff_left h₁).mpr h₂
 -/
 #guard_msgs in
 example {a b c : Nat} (h₁ : a ∣ c) (h₂ : a ∣ b + c) : a ∣ b := by apply?
@@ -271,14 +270,14 @@ axiom F (a b : Nat) : f a ≤ f b ↔ a ≤ b
 
 /--
 info: Try this:
-  exact (F a b).mpr h
+  [apply] exact (F a b).mpr h
 -/
 #guard_msgs in
 example (a b : Nat) (h : a ≤ b) : f a ≤ f b := by apply?
 
 /--
 info: Try this:
-  exact L.flatten
+  [apply] exact L.flatten
 -/
 #guard_msgs in
 example (L : List (List Nat)) : List Nat := by apply? using L
@@ -306,7 +305,7 @@ theorem Bool_eq_iff {A B : Bool} : (A = B) = (A ↔ B) :=
 
 /--
 info: Try this:
-  exact Bool_eq_iff
+  [apply] exact Bool_eq_iff
 -/
 #guard_msgs in
 theorem Bool_eq_iff2 {A B : Bool} : (A = B) = (A ↔ B) := by
@@ -347,7 +346,7 @@ theorem Bool_eq_iff2 {A B : Bool} : (A = B) = (A ↔ B) := by
 
 /--
 info: Try this:
-  refine Int.mul_ne_zero ?_ h
+  [apply] refine Int.mul_ne_zero ?_ h
   -- Remaining subgoals:
   -- ⊢ 2 ≠ 0
 ---
@@ -361,7 +360,7 @@ example {x : Int} (h : x ≠ 0) : 2 * x ≠ 0 := by
 -- https://leanprover.zulipchat.com/#narrow/stream/287929-mathlib4/topic/.60exact.3F.60.20failure.3A.20.22maximum.20recursion.20depth.20has.20been.20reached.22/near/417649319
 /--
 info: Try this:
-  exact Nat.add_comm n m
+  [apply] exact Nat.add_comm n m
 -/
 #guard_msgs in
 example (_h : List.range 10000 = List.range 10000) (n m : Nat) : n + m = m + n := by

tests/lean/librarySearch.lean.expected.out

@@ -1 +1 @@
-librarySearch.lean:384:0-384:7: warning: declaration uses 'sorry'
+librarySearch.lean:383:0-383:7: warning: declaration uses 'sorry'

tests/lean/run/3501.lean

@@ -1,6 +1,6 @@
 /--
 info: Try this:
-  simp only [Nat.reduceMul, a]
+  [apply] simp only [Nat.reduceMul, a]
 -/
 #guard_msgs in
 example : True := by

tests/lean/run/3519.lean

@@ -1,6 +1,6 @@
 /--
 info: Try this:
-  simp only [x]
+  [apply] simp only [x]
 ---
 warning: declaration uses 'sorry'
 -/
@@ -12,7 +12,7 @@ example {P : Nat → Prop} : let x := 0; P x := by
 
 /--
 info: Try this:
-  simp_all only [x]
+  [apply] simp_all only [x]
 ---
 warning: declaration uses 'sorry'
 -/

tests/lean/run/3547.lean

@@ -5,7 +5,7 @@ decreasing_by decreasing_tactic
 
 /--
 info: Try this:
-  simp only [foo]
+  [apply] simp only [foo]
 -/
 #guard_msgs in
 def foo2 : foo 2 = 0 := by

tests/lean/run/3710.lean

@@ -24,7 +24,7 @@ theorem indicator_of_not {s : Set} {a : Nat} (h : ¬ s a) : indicator s a = 0 :=
 
 /--
 info: Try this:
-  simp only [compl_iff, singleton_iff, not_true_eq_false, not_false_eq_true, indicator_of_not]
+  [apply] simp only [compl_iff, singleton_iff, not_true_eq_false, not_false_eq_true, indicator_of_not]
 -/
 #guard_msgs in
 theorem test : indicator (compl <| singleton 0) 0 = 0 := by

tests/lean/run/3922.lean

@@ -19,7 +19,7 @@ axiom r.trans {a b c : Nat} : r a b → r b c → r a c
 
 /--
 info: Try this:
-  refine r.symm ?_
+  [apply] refine r.symm ?_
   -- Remaining subgoals:
   -- ⊢ r a c
 ---
@@ -39,7 +39,7 @@ attribute [symm] r.symm
 
 /--
 info: Try this:
-  exact r.trans (id (r.symm h₂)) h₁
+  [apply] exact r.trans (id (r.symm h₂)) h₁
 -/
 #guard_msgs in
 example (a b c : Nat) (h₁ : r b a) (h₂ : r b c) : r c a := by

tests/lean/run/4230.lean

@@ -7,7 +7,7 @@ termination_by input.size - curr
 
 /--
 info: Try this:
-  termination_by input.size - curr
+  [apply] termination_by input.size - curr
 -/
 #guard_msgs(drop warning, info) in
 theorem foo (curr : Nat) (input : Array Nat) (output : Array Nat)

tests/lean/run/4251.lean

@@ -1,6 +1,6 @@
 /--
 info: Try this:
-  simp only [ha, Nat.reduceEqDiff, imp_self]
+  [apply] simp only [ha, Nat.reduceEqDiff, imp_self]
 -/
 #guard_msgs in
 theorem foo₁ (a : Nat) (ha : a = 37) :

tests/lean/run/4534.lean

@@ -13,7 +13,7 @@ instance : MyClass Prop where
 
 /--
 info: Try this:
-  simp only [MyClass.le_refl, MyClass.sup_of_le_left]
+  [apply] simp only [MyClass.le_refl, MyClass.sup_of_le_left]
 -/
 #guard_msgs in
 example : MyClass.sup False False = False := by

tests/lean/run/5407.lean

@@ -40,7 +40,7 @@ axiom a : A
 axiom b : B
 /--
 info: Try this:
-  (expose_names; exact imp h_1 h)
+  [apply] (expose_names; exact imp h_1 h)
 -/
 #guard_msgs in
 example : C := by
@@ -66,7 +66,7 @@ example : EqExplicit (fun (f : α → β) => (fun g x => g x) f) id := by
 /-! Suggests `expose_names` if a name in the syntax contains macro scopes -/
 /--
 info: Try this:
-  (expose_names; exact h)
+  [apply] (expose_names; exact h)
 -/
 #guard_msgs in
 example {P : Prop} : P → P := by
@@ -79,7 +79,7 @@ opaque D : Nat → Type
 axiom c_of_d {n : Nat} : D n → C
 /--
 info: Try this:
-  exact c_of_d x
+  [apply] exact c_of_d x
 -/
 #guard_msgs in
 example : (n : Nat) → D n → C := by
@@ -94,7 +94,7 @@ axiom option1 : A → E
 axiom option2 {_ : B} : E
 /--
 info: Try this:
-  refine option1 ?_
+  [apply] refine option1 ?_
   -- Remaining subgoals:
   -- ⊢ A
 ---
@@ -117,7 +117,7 @@ opaque R : A → B → Prop
 axiom rImp (b : B) : R a b → R a b
 /--
 info: Try this:
-  (expose_names; refine rImp b ?_)
+  [apply] (expose_names; refine rImp b ?_)
   -- Remaining subgoals:
   -- ⊢ R a b
 ---
@@ -132,7 +132,7 @@ example : (b : B) → R a b := by
 /-! `show_term` exhibits the same behavior as `exact?` -/
 /--
 info: Try this:
-  (expose_names; exact h)
+  [apply] (expose_names; exact h)
 -/
 #guard_msgs in
 example : E → E := by
@@ -154,7 +154,7 @@ example : B → E := by
   show_term apply option2
 /--
 info: Try this:
-  exact c_of_d d
+  [apply] exact c_of_d d
 -/
 #guard_msgs in
 example : (n : Nat) → D n → C := by
@@ -174,7 +174,7 @@ axiom eq (a' : A) : a = a'
 
 /--
 info: Try this:
-  (expose_names; rw [eq a'])
+  [apply] (expose_names; rw [eq a'])
   -- Foo a' a'
 ---
 error: unsolved goals

tests/lean/run/5634.lean

@@ -86,14 +86,14 @@ Regression test: make sure `simpa?` reports lemmas for both the goal and the `us
 
 /--
 info: Try this:
-  simpa only [id] using h
+  [apply] simpa only [id] using h
 -/
 #guard_msgs in example (p : Prop) (h : p) : id p := by
   simpa? only [id] using h
 
 /--
 info: Try this:
-  simpa only [id] using h
+  [apply] simpa only [id] using h
 -/
 #guard_msgs in example (p : Prop) (h : id p) : p := by
   simpa? only [id] using h

tests/lean/run/5993.lean

@@ -12,7 +12,7 @@ No field notation notation here. Used to print `refine ?_.succ` and `refine ?_.s
 
 /--
 info: Try this:
-  refine Nat.succ ?_
+  [apply] refine Nat.succ ?_
 ---
 info: found a partial proof, but the corresponding tactic failed:
   (expose_names; refine Prod.snd ?_)
@@ -31,7 +31,7 @@ No field notation even under binders. (That is, be aware of delayed assignment m
 
 /--
 info: Try this:
-  refine fun x => Nat.succ ?_
+  [apply] refine fun x => Nat.succ ?_
 -/
 #guard_msgs in
 example : Nat → Nat := by

tests/lean/run/6164.lean

@@ -9,7 +9,7 @@ attribute [simp] Nat.two_mul
 
 /--
 info: Try this:
-  simp only [Nat.two_mul]
+  [apply] simp only [Nat.two_mul]
 -/
 #guard_msgs in
 example (n : Nat) : 123 + 2 * n = 123 + (n + n) := by
@@ -22,7 +22,7 @@ example (n : Nat) : 123 + 2 * n = 123 + (n + n) := by
 
 /--
 info: Try this:
-  dsimp only [foo]
+  [apply] dsimp only [foo]
 -/
 #guard_msgs in
 example (n : Nat) : foo n = n + 1 := by

tests/lean/run/6655.lean

@@ -18,7 +18,7 @@ Example from #6655. This used to suggest `simp only [e, d]`.
 -/
 /--
 info: Try this:
-  simp only [e]
+  [apply] simp only [e]
 ---
 trace: α : Type
 c : α → α
@@ -43,7 +43,7 @@ Example from #6655. This used to suggest `simp only [d]`.
 -/
 /--
 info: Try this:
-  simp only
+  [apply] simp only
 ---
 warning: declaration uses 'sorry'
 -/
@@ -62,7 +62,7 @@ Example from comments of #6655. This used to suggest `simp only [Int.add_sub_can
 -/
 /--
 info: Try this:
-  simp only [Int.add_sub_cancel]
+  [apply] simp only [Int.add_sub_cancel]
 -/
 #guard_msgs in
 example (a b : Int) : a + b - b = a := by
@@ -77,10 +77,10 @@ This used to suggest `simp only [a, b] ` and `simp only [a, b]`
 -/
 /--
 info: Try this:
-  simp only [a]
+  [apply] simp only [a]
 ---
 info: Try this:
-  simp only
+  [apply] simp only
 -/
 #guard_msgs in
 example : True := by
@@ -96,7 +96,7 @@ Test that there is still a deficiency. This should say `simp only [e]`.
 -/
 /--
 info: Try this:
-  simp only [e, c]
+  [apply] simp only [e, c]
 ---
 trace: α : Type
 b : α → α

tests/lean/run/6706.lean

@@ -11,7 +11,7 @@ def P := True
 theorem N.A.B : P := trivial
 /--
 info: Try this:
-  simp only [N.A.B]
+  [apply] simp only [N.A.B]
 -/
 #guard_msgs in
 theorem N.X.A.B : P := by
@@ -19,7 +19,7 @@ theorem N.X.A.B : P := by
 
 /--
 info: Try this:
-  simp only [_root_.N.A.B]
+  [apply] simp only [_root_.N.A.B]
 -/
 #guard_msgs in
 theorem A : P :=

tests/lean/run/7927.lean

@@ -6,21 +6,21 @@ example : f true = true := by simp!
 
 /--
 info: Try this:
-  simp! only [f]
+  [apply] simp! only [f]
 -/
 #guard_msgs in
 example : f true = true := by simp?!
 
 /--
 info: Try this:
-  simp_all! only [f]
+  [apply] simp_all! only [f]
 -/
 #guard_msgs in
 example : f true = true := by simp_all?!
 
 /--
 info: Try this:
-  dsimp! only [f]
+  [apply] dsimp! only [f]
 -/
 #guard_msgs in
 example : f true = true := by dsimp?!

tests/lean/run/allGoals.lean

@@ -125,8 +125,8 @@ but is expected to have type
   false = false
 ---
 info: Try this:
-  Bool.casesOn (motive := fun t => b = t → b = b) b
-    (fun h => Eq.symm h ▸ sorry) (fun h => Eq.symm h ▸ Eq.refl true) (Eq.refl b)
+  [apply] Bool.casesOn (motive := fun t => b = t → b = b) b (fun h => Eq.symm h ▸ sorry)
+    (fun h => Eq.symm h ▸ Eq.refl true) (Eq.refl b)
 -/
 #guard_msgs in
 example (b : Bool) : b = b := by?
@@ -221,7 +221,7 @@ error: Failed: `fail` tactic was invoked
 ⊢ True
 ---
 info: Try this:
-  sorry
+  [apply] sorry
 -/
 #guard_msgs in
 example : True := by?
@@ -241,7 +241,7 @@ use `set_option maxRecDepth <num>` to increase limit
 use `set_option diagnostics true` to get diagnostic information
 ---
 info: Try this:
-  sorry
+  [apply] sorry
 -/
 #guard_msgs in
 example : True := by?

tests/lean/run/grind_constProp.lean

@@ -209,7 +209,7 @@ def evalExpr (e : Expr) : EvalM Val := do
 
 /--
 info: Try this:
-  fun_induction Expr.simplify <;> grind
+  [apply] (fun_induction Expr.simplify) <;> grind
 -/
 #guard_msgs (info) in
 example (e : Expr) : e.simplify.eval σ = e.eval σ := by
@@ -311,7 +311,7 @@ theorem State.cons_le_of_eq (h₁ : σ' ≼ σ) (h₂ : σ.find? x = some v) : (
 
 /--
 info: Try this:
-  fun_induction join <;> grind
+  [apply] (fun_induction join) <;> grind
 -/
 #guard_msgs (info) in
 open State in

tests/lean/run/grind_ematch_gen_pattern.lean

@@ -10,7 +10,7 @@ example (h : b = some a) : (b.pbind fun a h => some <| a + f b (by grind)) = som
 
 /--
 info: Try this:
-  grind only [= gen Option.pbind_some', f, cases Or]
+  [apply] grind only [= gen Option.pbind_some', f, cases Or]
 -/
 #guard_msgs (info) in
 example (h : b = some a) : (b.pbind fun a h => some <| a + f b (by grind)) = some (a + a) := by

tests/lean/run/grind_eval_suggest.lean

@@ -15,10 +15,10 @@ opaque f : Nat → Nat
 
 /--
 info: Try these:
-  • simp +arith
-  • simp +arith only [Nat.reduceAdd, fthm]
-  • grind
-  • grind only [= fthm]
+  [apply] simp +arith
+  [apply] simp +arith only [Nat.reduceAdd, fthm]
+  [apply] grind
+  [apply] grind only [= fthm]
 -/
 #guard_msgs (info) in
 example (x : Nat) : 1 + 1 + f x = x + 2 := by
@@ -26,11 +26,11 @@ example (x : Nat) : 1 + 1 + f x = x + 2 := by
 
 /--
 info: Try these:
-  • rfl
-  • simp
-  • simp only [Nat.succ_eq_add_one, Nat.add_left_cancel_iff]
-  • grind
-  • grind only
+  [apply] rfl
+  [apply] simp
+  [apply] simp only [Nat.succ_eq_add_one, Nat.add_left_cancel_iff]
+  [apply] grind
+  [apply] grind only
 -/
 #guard_msgs (info) in
 example (x : Nat) : x + 1 = Nat.succ x := by
@@ -38,11 +38,11 @@ example (x : Nat) : x + 1 = Nat.succ x := by
 
 /--
 info: Try these:
-  • · intros; rfl
-  • · intros; simp
-  • · intros; simp only [Nat.succ_eq_add_one, Nat.add_left_cancel_iff]
-  • · intros; grind
-  • · intros; grind only
+  [apply] · intros; rfl
+  [apply] · intros; simp
+  [apply] · intros; simp only [Nat.succ_eq_add_one, Nat.add_left_cancel_iff]
+  [apply] · intros; grind
+  [apply] · intros; grind only
 -/
 #guard_msgs (info) in
 example (x : Nat) : True → x + 1 = Nat.succ x := by
@@ -50,9 +50,9 @@ example (x : Nat) : True → x + 1 = Nat.succ x := by
 
 /--
 info: Try these:
-  • simp_all
-  • grind
-  • grind only
+  [apply] simp_all
+  [apply] grind
+  [apply] grind only
 -/
 #guard_msgs (info) in
 example (h : 0 + x = y) : f x = f y := by
@@ -74,7 +74,7 @@ macro "simple_tac" : tactic => `(tactic| eval_suggest (intros; skip; first | ski
 
 /--
 info: Try this:
-  simp
+  [apply] simp
 -/
 #guard_msgs (info) in
 example : True ∧ True := by
@@ -89,7 +89,7 @@ macro "simple_tac2" : tactic => `(tactic| eval_suggest (intros; (simp only [Nat.
 
 /--
 info: Try this:
-  · intros; simp only [Nat.zero_add]; simp only [Nat.one_mul]; simp [*]
+  [apply] · intros; simp only [Nat.zero_add]; simp only [Nat.one_mul]; simp [*]
 -/
 #guard_msgs (info) in
 example : x = 0 → 0 + 1*x = 0 := by

tests/lean/run/grind_option.lean

@@ -9,32 +9,29 @@ variable [BEq α] {o₁ o₂ o₃ o₄ o₅ : Option α}
 
 /--
 info: Try this:
-  grind only [=
-      Option.or_some,
-    = Option.some_beq_none, = Option.getD_or, = Option.some_or, =_ Option.or_assoc, = Option.or_assoc]
+  [apply] grind only [= Option.or_some, = Option.some_beq_none, = Option.getD_or, = Option.some_or, =_ Option.or_assoc,
+    = Option.or_assoc]
 -/
 #guard_msgs in
 example : ((o₁.or (o₂.or (some x))).or (o₄.or o₅) == none) = false := by grind?
 
 /--
 info: Try this:
-  grind only [= Option.max_none_right,
-    = Option.min_some_some, = Nat.min_def]
+  [apply] grind only [= Option.max_none_right, = Option.min_some_some, = Nat.min_def]
 -/
 #guard_msgs in
 example : max (some 7) none = min (some 13) (some 7) := by grind?
 
 /--
 info: Try this:
-  grind only [= Option.guard_apply]
+  [apply] grind only [= Option.guard_apply]
 -/
 #guard_msgs in
 example : Option.guard (· ≤ 7) 3 = some 3 := by grind?
 
 /--
 info: Try this:
-  grind only [=
-      Option.mem_bind_iff]
+  [apply] grind only [= Option.mem_bind_iff]
 -/
 #guard_msgs in
 example {x : β} {o : Option α} {f : α → Option β} (h : a ∈ o) (h' : x ∈ f a) : x ∈ o.bind f := by grind?

tests/lean/run/grind_pat_sel.lean

@@ -64,35 +64,35 @@ opaque r : Nat → Nat → Nat
 
 /--
 info: Try these:
-  • [grind! .] for pattern: [r #2 (f #1)]
-  • [grind! =>] for pattern: [f #2, f #1]
+  [apply] [grind! .] for pattern: [r #2 (f #1)]
+  [apply] [grind! =>] for pattern: [f #2, f #1]
 -/
 #guard_msgs in
 @[grind!] theorem pr₅ : p (f x) → r x (f y) = y := sorry
 
 /--
 info: Try these:
-  • [grind! .] for pattern: [f #1, f #2]
-  • [grind! =>] for pattern: [f #2, f #1]
+  [apply] [grind! .] for pattern: [f #1, f #2]
+  [apply] [grind! =>] for pattern: [f #2, f #1]
 -/
 #guard_msgs in
 @[grind!] theorem pr₆ : p (f x) → r y (f y) = y := sorry
 
 /--
 info: Try these:
-  • [grind .] for pattern: [r #1 (f #1), p (f #2)]
-  • [grind =>] for pattern: [p (f #2), r #1 (f #1)]
-  • [grind! .] for pattern: [f #1, f #2]
-  • [grind! =>] for pattern: [f #2, f #1]
+  [apply] [grind .] for pattern: [r #1 (f #1), p (f #2)]
+  [apply] [grind =>] for pattern: [p (f #2), r #1 (f #1)]
+  [apply] [grind! .] for pattern: [f #1, f #2]
+  [apply] [grind! =>] for pattern: [f #2, f #1]
 -/
 #guard_msgs in
 @[grind] theorem pr₇ : p (f x) → r y (f y) = y := sorry
 
 /--
 info: Try these:
-  • [grind =] for pattern: [r #2 (f #1)]
-  • [grind =>] for pattern: [p (f #2), r #2 (f #1)]
-  • [grind! =>] for pattern: [f #2, f #1]
+  [apply] [grind =] for pattern: [r #2 (f #1)]
+  [apply] [grind =>] for pattern: [p (f #2), r #2 (f #1)]
+  [apply] [grind! =>] for pattern: [f #2, f #1]
 -/
 #guard_msgs in
 @[grind] theorem pr₈ : p (f x) → r x (f y) = y := sorry
@@ -100,24 +100,24 @@ info: Try these:
 
 /--
 info: Try these:
-  • [grind =] for pattern: [f (g #0)]
-  • [grind! .] for pattern: [g #0]
+  [apply] [grind =] for pattern: [f (g #0)]
+  [apply] [grind! .] for pattern: [g #0]
 -/
 #guard_msgs in
 @[grind] axiom fg₆ : f (g x) = x
 
 /--
 info: Try these:
-  • [grind =] for pattern: [f (g #0)]
-  • [grind =_] for pattern: [r #0 #0]
-  • [grind! .] for pattern: [g #0]
+  [apply] [grind =] for pattern: [f (g #0)]
+  [apply] [grind =_] for pattern: [r #0 #0]
+  [apply] [grind! .] for pattern: [g #0]
 -/
 #guard_msgs in
 @[grind] axiom fg₇ : f (g x) = r x x
 
 /--
 info: Try this:
-  [grind =] for pattern: [f #0]
+  [apply] [grind =] for pattern: [f #0]
 -/
 #guard_msgs in
 @[grind] axiom fg₈ : f x = x

tests/lean/run/grind_trace.lean

@@ -21,7 +21,7 @@ attribute [grind =] List.getElem?_cons_zero in
 
 /--
 info: Try this:
-  grind only [= List.getElem?_eq_none, = List.getElem?_replicate, = List.getElem?_eq_getElem]
+  [apply] grind only [= List.getElem?_eq_none, = List.getElem?_replicate, = List.getElem?_eq_getElem]
 -/
 #guard_msgs (info) in
 theorem getElem?_replicate' : (List.replicate n a)[m]? = if m < n then some a else none := by
@@ -29,7 +29,7 @@ theorem getElem?_replicate' : (List.replicate n a)[m]? = if m < n then some a el
 
 /--
 info: Try this:
-  grind only [= List.length_cons]
+  [apply] grind only [= List.length_cons]
 -/
 #guard_msgs (info) in
 example : 0 < (x :: t).length := by
@@ -38,9 +38,9 @@ example : 0 < (x :: t).length := by
 attribute [grind ext] List.ext_getElem?
 /--
 info: Try this:
-  grind only [= List.getElem?_eq_some_iff, = List.length_replicate, = List.getElem?_eq_none,
-      = List.getElem_replicate, = Option.map_some, = Option.map_none, = List.getElem?_replicate,
-      = List.getElem?_eq_getElem, = List.getElem?_map]
+  [apply] grind only [= List.getElem?_eq_some_iff, = List.length_replicate, = List.getElem?_eq_none,
+    = List.getElem_replicate, = Option.map_some, = Option.map_none, = List.getElem?_replicate,
+    = List.getElem?_eq_getElem, = List.getElem?_map]
 -/
 #guard_msgs (info) in
 theorem map_replicate' : (List.replicate n a).map f = List.replicate n (f a) := by
@@ -48,7 +48,7 @@ theorem map_replicate' : (List.replicate n a).map f = List.replicate n (f a) :=
 
 /--
 info: Try this:
-  grind only [= List.getLast?_eq_some_iff, ← List.mem_concat_self]
+  [apply] grind only [= List.getLast?_eq_some_iff, ← List.mem_concat_self]
 -/
 #guard_msgs (info) in
 theorem mem_of_getLast?_eq_some' {xs : List α} {a : α} (h : xs.getLast? = some a) : a ∈ xs := by
@@ -60,7 +60,7 @@ theorem mem_of_getLast?_eq_some' {xs : List α} {a : α} (h : xs.getLast? = some
 
 /--
 info: Try this:
-  grind only
+  [apply] grind only
 -/
 #guard_msgs (info) in
 example : x = 0 → f x = 1 := by
@@ -71,7 +71,7 @@ attribute [grind] f
 
 /--
 info: Try this:
-  grind only [f]
+  [apply] grind only [f]
 -/
 #guard_msgs (info) in
 example : x = 0 → f x = 1 := by
@@ -85,7 +85,7 @@ grind_pattern gthm => g (g x)
 
 /--
 info: Try this:
-  grind only [usr gthm]
+  [apply] grind only [usr gthm]
 -/
 #guard_msgs (info) in
 example : g (g (g x)) = g x := by

tests/lean/run/grind_try_exact.lean

@@ -7,7 +7,7 @@ theorem Pall : Q x → P x := sorry
 
 /--
 info: Try this:
-  exact Pall h
+  [apply] exact Pall h
 -/
 #guard_msgs (info) in
 example (h : Q x) (_ : x > 0) : P x := by
@@ -15,7 +15,7 @@ example (h : Q x) (_ : x > 0) : P x := by
 
 /--
 info: Try this:
-  · intros; expose_names; exact Pall h
+  [apply] · intros; expose_names; exact Pall h
 -/
 #guard_msgs (info) in
 example: Q x → True → P x := by
@@ -23,7 +23,7 @@ example: Q x → True → P x := by
 
 /--
 info: Try this:
-  · intros; expose_names; exact Pall h_1
+  [apply] · intros; expose_names; exact Pall h_1
 -/
 #guard_msgs (info) in
 example: True → Q x → True → P x := by
@@ -43,7 +43,7 @@ example : Q x := by
 
 /--
 info: Try this:
-  · expose_names; exact Pall h
+  [apply] · expose_names; exact Pall h
 -/
 #guard_msgs (info) in
 example (_ : Q x) (_ : x > 0) : P x := by

tests/lean/run/grind_try_extend.lean

@@ -13,7 +13,7 @@ meta def evalTryApply : TryTactic := fun tac => do
 
 /--
 info: Try this:
-  · trace "worked"; assumption
+  [apply] · trace "worked"; assumption
 -/
 #guard_msgs (info) in
 example (h : False) : False := by
@@ -28,8 +28,8 @@ elab stx:"my_try?" : tactic => do
 
 /--
 info: Try these:
-  • · trace "worked"; assumption
-  • rfl
+  [apply] · trace "worked"; assumption
+  [apply] rfl
 -/
 #guard_msgs (info) in
 example (a : Nat) (h : a = a) : a = a := by

tests/lean/run/grind_try_trace.lean

@@ -4,11 +4,11 @@ reset_grind_attrs%
 
 /--
 info: Try these:
-  • simp
-  • simp only [ne_eq, reduceCtorEq, not_false_eq_true]
-  • grind
-  • grind only
-  • simp_all
+  [apply] simp
+  [apply] simp only [ne_eq, reduceCtorEq, not_false_eq_true]
+  [apply] grind
+  [apply] grind only
+  [apply] simp_all
 -/
 #guard_msgs (info) in
 example : [1, 2] ≠ [] := by
@@ -16,10 +16,10 @@ example : [1, 2] ≠ [] := by
 
 /--
 info: Try these:
-  • simp +arith
-  • simp +arith only [ge_iff_le]
-  • grind
-  • grind only
+  [apply] simp +arith
+  [apply] simp +arith only [ge_iff_le]
+  [apply] grind
+  [apply] grind only
 -/
 #guard_msgs (info) in
 example : 4 + x + y ≥ 1 + x  := by
@@ -27,8 +27,8 @@ example : 4 + x + y ≥ 1 + x  := by
 
 /--
 info: Try these:
-  • simp +arith
-  • grind
+  [apply] simp +arith
+  [apply] grind
 -/
 #guard_msgs (info) in
 example : 4 + x + y ≥ 1 + x  := by
@@ -36,8 +36,8 @@ example : 4 + x + y ≥ 1 + x  := by
 
 /--
 info: Try these:
-  • grind
-  • grind only
+  [apply] grind
+  [apply] grind only
 -/
 #guard_msgs (info) in
 example (f : Nat → Nat) : f a = b → a = c → f c = b := by
@@ -49,8 +49,8 @@ public def f : Nat → Nat
 
 /--
 info: Try these:
-  • grind [= f]
-  • grind only [f]
+  [apply] grind [= f]
+  [apply] grind only [f]
 -/
 #guard_msgs (info) in
 example : f (f 0) > 0 := by
@@ -58,8 +58,8 @@ example : f (f 0) > 0 := by
 
 /--
 info: Try these:
-  • grind [= f.eq_def]
-  • grind only [= f.eq_def]
+  [apply] grind [= f.eq_def]
+  [apply] grind only [= f.eq_def]
 -/
 #guard_msgs (info) in
 example : f x > 0 := by
@@ -71,9 +71,9 @@ def app : List α → List α → List α
 
 /--
 info: Try these:
-  • rfl
-  • grind [= app]
-  • grind only [app]
+  [apply] rfl
+  [apply] grind [= app]
+  [apply] grind only [app]
 -/
 #guard_msgs (info) in
 example : app [a, b] [c] = [a, b, c] := by
@@ -81,8 +81,8 @@ example : app [a, b] [c] = [a, b, c] := by
 
 /--
 info: Try these:
-  • fun_induction app as bs <;> grind [= app]
-  • fun_induction app as bs <;> grind only [app]
+  [apply] (fun_induction app as bs) <;> grind [= app]
+  [apply] (fun_induction app as bs) <;> grind only [app]
 -/
 #guard_msgs (info) in
 example : app (app as bs) cs = app as (app bs cs) := by
@@ -90,7 +90,7 @@ example : app (app as bs) cs = app as (app bs cs) := by
 
 /--
 info: Try this:
-  fun_induction app as bs <;> grind [= app]
+  [apply] (fun_induction app as bs) <;> grind [= app]
 -/
 #guard_msgs (info) in
 example : app (app as bs) cs = app as (app bs cs) := by
@@ -98,8 +98,8 @@ example : app (app as bs) cs = app as (app bs cs) := by
 
 /--
 info: Try these:
-  • · expose_names; fun_induction app as bs_1 <;> grind [= app]
-  • · expose_names; fun_induction app as bs_1 <;> grind only [app]
+  [apply] · expose_names; fun_induction app as bs_1 <;> grind [= app]
+  [apply] · expose_names; fun_induction app as bs_1 <;> grind only [app]
 -/
 #guard_msgs (info) in
 example : app (app as bs) cs = app as (app bs cs) := by
@@ -108,8 +108,8 @@ example : app (app as bs) cs = app as (app bs cs) := by
 
 /--
 info: Try these:
-  • · expose_names; fun_induction app as bs <;> grind [= app]
-  • · expose_names; fun_induction app as bs <;> grind only [app]
+  [apply] · expose_names; fun_induction app as bs <;> grind [= app]
+  [apply] · expose_names; fun_induction app as bs <;> grind only [app]
 -/
 #guard_msgs (info) in
 example : app (app as bs) cs = app as (app bs cs) := by
@@ -126,8 +126,8 @@ attribute [simp] concat
 
 /--
 info: Try these:
-  • fun_induction concat <;> simp_all
-  • fun_induction concat <;> simp [*]
+  [apply] (fun_induction concat) <;> simp_all
+  [apply] (fun_induction concat) <;> simp [*]
 -/
 #guard_msgs (info) in
 example (as : List α) (a : α) : concat as a = as ++ [a] := by
@@ -135,10 +135,11 @@ example (as : List α) (a : α) : concat as a = as ++ [a] := by
 
 /--
 info: Try these:
-  • fun_induction concat <;> simp_all
-  • · fun_induction concat
-        · simp
-        · simp [*]
+  [apply] (fun_induction concat) <;> simp_all
+  [apply] ·
+    fun_induction concat
+    · simp
+    · simp [*]
 -/
 #guard_msgs (info) in
 example (as : List α) (a : α) : concat as a = as ++ [a] := by
@@ -150,8 +151,8 @@ def map (f : α → β) : List α → List β
 
 /--
 info: Try these:
-  • fun_induction map f xs <;> grind [= map]
-  • fun_induction map f xs <;> grind only [map]
+  [apply] (fun_induction map f xs) <;> grind [= map]
+  [apply] (fun_induction map f xs) <;> grind only [map]
 -/
 #guard_msgs (info) in
 theorem map_map (f : α → β) (g : β → γ) xs :
@@ -165,15 +166,18 @@ def foo : Nat → Nat
 
 /--
 info: Try these:
-  • · fun_induction foo
-        · simp
-        · sorry
-  • · fun_induction foo
-        · grind
-        · sorry
-  • · fun_induction foo
-        · simp_all
-        · sorry
+  [apply] ·
+    fun_induction foo
+    · simp
+    · sorry
+  [apply] ·
+    fun_induction foo
+    · grind
+    · sorry
+  [apply] ·
+    fun_induction foo
+    · simp_all
+    · sorry
 -/
 #guard_msgs (info) in
 example : foo x > 0 := by
@@ -198,11 +202,11 @@ attribute [grind] List.length_reverse bla
 
 /--
 info: Try these:
-  • fun_induction bla <;> grind
-  • fun_induction bla <;> simp_all
-  • fun_induction bla <;> simp [*]
-  • fun_induction bla <;> simp only [List.length_reverse, *]
-  • fun_induction bla <;> grind only [= List.length_reverse]
+  [apply] (fun_induction bla) <;> grind
+  [apply] (fun_induction bla) <;> simp_all
+  [apply] (fun_induction bla) <;> simp [*]
+  [apply] (fun_induction bla) <;> simp only [List.length_reverse, *]
+  [apply] (fun_induction bla) <;> grind only [= List.length_reverse]
 -/
 #guard_msgs (info) in
 example : (bla xs ys).length = ys.length := by

tests/lean/run/info_trees.lean

@@ -70,7 +70,7 @@ info: • [Command] @ ⟨77, 0⟩-⟨77, 40⟩ @ Lean.Elab.Command.elabDeclarati
     • [Term] t (isBinder := true) : ∀ (n : Nat), 0 ≤ n @ ⟨77, 8⟩-⟨77, 9⟩
 ---
 info: Try this:
-  exact Nat.zero_le n
+  [apply] exact Nat.zero_le n
 -/
 #guard_msgs in
 #info_trees in

tests/lean/run/issue8257.lean

@@ -1,6 +1,6 @@
 /--
 info: Try this:
-  termination_by xs.length / 2 - i
+  [apply] termination_by xs.length / 2 - i
 -/
 #guard_msgs in
 def foo (xs : String) (i : Nat) (a b : String.Iterator) : Bool :=
@@ -14,7 +14,7 @@ termination_by?
 
 /--
 info: Try this:
-  termination_by xs.length / 2 - i
+  [apply] termination_by xs.length / 2 - i
 -/
 #guard_msgs in
 def bar (xs : String) (i : Nat) (a b : String.Iterator) : Bool :=
@@ -30,7 +30,7 @@ termination_by?
 
 /--
 info: Try this:
-  termination_by xs.length / 2 - i
+  [apply] termination_by xs.length / 2 - i
 -/
 #guard_msgs in
 def baz (xs : String) (i : Nat) (a b : String.Iterator) : Bool :=

tests/lean/run/issue8490.lean

@@ -14,7 +14,7 @@ inductive_fixpoint
 
 /--
 info: Try this:
-  simp_all only [asimp_const, reduceCtorEq]
+  [apply] simp_all only [asimp_const, reduceCtorEq]
 -/
 #guard_msgs in
 example (x y : Aexp) (k : Int) (h : asimp_const (.val k) = x.plus y) : optimal' x := by

tests/lean/run/issue8939.lean

@@ -11,7 +11,7 @@ public inductive AckFuel : (n m : Nat) → Type where
 namespace Test1
 /--
 info: Try this:
-  termination_by structural x _ x => x
+  [apply] termination_by structural x _ x => x
 -/
 #guard_msgs in
 public def ackermann_fuel : (n m : Nat) → (fuel : AckFuel n m) → Nat
@@ -25,7 +25,7 @@ end Test1
 namespace Test2
 /--
 info: Try this:
-  termination_by structural x _ x => x
+  [apply] termination_by structural x _ x => x
 -/
 #guard_msgs in
 public def ackermann_fuel : (n m : Nat) → (fuel : AckFuel n m) → Nat
@@ -39,7 +39,7 @@ end Test2
 namespace Test3
 /--
 info: Try this:
-  termination_by structural x _ x => x
+  [apply] termination_by structural x _ x => x
 -/
 #guard_msgs in
 @[expose] public def ackermann_fuel : (n m : Nat) → (fuel : AckFuel n m) → Nat

tests/lean/run/mvcgenInvariantsSuggestions.lean

@@ -16,8 +16,8 @@ def mySum (l : List Nat) : Nat := Id.run do
 
 /--
 info: Try this:
-  invariants
-    · ⇓⟨xs, letMuts⟩ => ⌜xs.prefix = [] ∧ letMuts = 0 ∨ xs.suffix = [] ∧ letMuts = l.sum⌝
+  [apply] invariants
+  · ⇓⟨xs, letMuts⟩ => ⌜xs.prefix = [] ∧ letMuts = 0 ∨ xs.suffix = [] ∧ letMuts = l.sum⌝
 -/
 #guard_msgs (info) in
 theorem mySum_suggest_invariant (l : List Nat) : mySum l = l.sum := by
@@ -36,8 +36,8 @@ def mySum2 (l : List Nat) : Nat := Id.run do
 
 /--
 info: Try this:
-  invariants
-    · ⇓⟨xs, letMuts⟩ => ⌜xs.prefix = [] ∧ letMuts = ⟨0, 0⟩ ∨ xs.suffix = [] ∧ letMuts.fst = l.sum⌝
+  [apply] invariants
+  · ⇓⟨xs, letMuts⟩ => ⌜xs.prefix = [] ∧ letMuts = ⟨0, 0⟩ ∨ xs.suffix = [] ∧ letMuts.fst = l.sum⌝
 -/
 #guard_msgs (info) in
 theorem mySum2_suggest_invariant (l : List Nat) : mySum2 l = l.sum := by
@@ -54,8 +54,8 @@ def copy (l : List Nat) : Id (Array Nat) := do
 
 /--
 info: Try this:
-  invariants
-    · ⇓⟨xs, letMuts⟩ => ⌜xs.prefix = [] ∧ letMuts = acc✝ ∨ xs.suffix = [] ∧ letMuts = l.toArray⌝
+  [apply] invariants
+  · ⇓⟨xs, letMuts⟩ => ⌜xs.prefix = [] ∧ letMuts = acc✝ ∨ xs.suffix = [] ∧ letMuts = l.toArray⌝
 -/
 #guard_msgs (info) in
 theorem copy_suggest_invariant (l : List Nat) : ⦃⌜True⌝⦄ copy l ⦃⇓ r => ⌜r = l.toArray⌝⦄ := by
@@ -79,10 +79,10 @@ def nodup (l : List Int) : Bool := Id.run do
 
 /--
 info: Try this:
-  invariants
-    ·
-      Invariant.withEarlyReturn (onReturn := fun r letMuts => ⌜l.Nodup ∧ (r = true ↔ l.Nodup)⌝)
-        (onContinue := fun xs letMuts => ⌜xs.prefix = [] ∧ letMuts = ∅ ∨ xs.suffix = [] ∧ l.Nodup⌝)
+  [apply] invariants
+  ·
+    Invariant.withEarlyReturn (onReturn := fun r letMuts => ⌜l.Nodup ∧ (r = true ↔ l.Nodup)⌝) (onContinue :=
+      fun xs letMuts => ⌜xs.prefix = [] ∧ letMuts = ∅ ∨ xs.suffix = [] ∧ l.Nodup⌝)
 -/
 #guard_msgs (info) in
 theorem nodup_suggest_invariant (l : List Int) : nodup l ↔ l.Nodup := by
@@ -106,19 +106,18 @@ def nodup_twice (l : List Int) : Bool := Id.run do
 
 /--
 info: Try this:
-  invariants
-    ·
-      Invariant.withEarlyReturn (onReturn := fun r letMuts =>
-        spred(Prod.fst ?inv2 ({ «prefix» := [], suffix := l, property := ⋯ }, ⟨none, ∅⟩) ∧
-            { down := r = true ↔ l.Nodup }))
-        (onContinue := fun xs letMuts =>
-        spred({ down := xs.prefix = [] ∧ letMuts = ∅ } ∨
-            ⌜xs.suffix = []⌝ ∧
-              Prod.fst ?inv2 ({ «prefix» := [], suffix := l, property := ⋯ }, ⟨none, ∅⟩) ∧
-                { down := True }))
-    ·
-      Invariant.withEarlyReturn (onReturn := fun r letMuts => ⌜l.Nodup ∧ (r = true ↔ l.Nodup)⌝)
-        (onContinue := fun xs letMuts => ⌜xs.prefix = [] ∧ letMuts = ∅ ∨ xs.suffix = [] ∧ l.Nodup⌝)
+  [apply] invariants
+  ·
+    Invariant.withEarlyReturn (onReturn := fun r letMuts =>
+      spred(Prod.fst ?inv2 ({ «prefix» := [], suffix := l, property := ⋯ }, ⟨none, ∅⟩) ∧
+          { down := r = true ↔ l.Nodup }))
+      (onContinue := fun xs letMuts =>
+      spred({ down := xs.prefix = [] ∧ letMuts = ∅ } ∨
+          ⌜xs.suffix = []⌝ ∧
+            Prod.fst ?inv2 ({ «prefix» := [], suffix := l, property := ⋯ }, ⟨none, ∅⟩) ∧ { down := True }))
+  ·
+    Invariant.withEarlyReturn (onReturn := fun r letMuts => ⌜l.Nodup ∧ (r = true ↔ l.Nodup)⌝) (onContinue :=
+      fun xs letMuts => ⌜xs.prefix = [] ∧ letMuts = ∅ ∨ xs.suffix = [] ∧ l.Nodup⌝)
 -/
 #guard_msgs (info) in
 theorem nodup_twice_suggest_invariant (l : List Int) : nodup_twice l ↔ l.Nodup := by
@@ -148,8 +147,8 @@ def mkFreshN (n : Nat) : AppM (List Nat) := do
 -- In the following, we suggest an inaccessible variable `acc` in the invariant. Unfortunate.
 /--
 info: Try this:
-  invariants
-    · ⇓⟨xs, letMuts⟩ => ⌜xs.prefix = [] ∧ letMuts = acc✝ ∨ xs.suffix = [] ∧ letMuts.toList.Nodup⌝
+  [apply] invariants
+  · ⇓⟨xs, letMuts⟩ => ⌜xs.prefix = [] ∧ letMuts = acc✝ ∨ xs.suffix = [] ∧ letMuts.toList.Nodup⌝
 -/
 #guard_msgs (info) in
 theorem mkFreshN_suggest_invariant (n : Nat) : ⦃⌜True⌝⦄ mkFreshN n ⦃⇓ r => ⌜r.Nodup⌝⦄ := by
@@ -166,11 +165,10 @@ def mkFreshN_early_return (n : Nat) : AppM (List Nat) := do
 
 /--
 info: Try this:
-  invariants
-    ·
-      Invariant.withEarlyReturn (onReturn := fun r letMuts => ⌜letMuts.toList.Nodup ∧ r.Nodup⌝)
-        (onContinue := fun xs letMuts =>
-        ⌜xs.prefix = [] ∧ letMuts = acc✝ ∨ xs.suffix = [] ∧ letMuts.toList.Nodup⌝)
+  [apply] invariants
+  ·
+    Invariant.withEarlyReturn (onReturn := fun r letMuts => ⌜letMuts.toList.Nodup ∧ r.Nodup⌝) (onContinue :=
+      fun xs letMuts => ⌜xs.prefix = [] ∧ letMuts = acc✝ ∨ xs.suffix = [] ∧ letMuts.toList.Nodup⌝)
 -/
 #guard_msgs (info) in
 theorem mkFreshN_early_return_suggest_invariant (n : Nat) : ⦃⌜True⌝⦄ mkFreshN_early_return n ⦃⇓ r => ⌜r.Nodup⌝⦄ := by
@@ -184,10 +182,10 @@ def earlyReturnWithoutLetMut (l : List Int) : Bool := Id.run do
 
 /--
 info: Try this:
-  invariants
-    ·
-      Invariant.withEarlyReturn (onReturn := fun r letMuts => ⌜r = true⌝) (onContinue :=
-        fun xs letMuts => ⌜xs.prefix = [] ∨ xs.suffix = []⌝)
+  [apply] invariants
+  ·
+    Invariant.withEarlyReturn (onReturn := fun r letMuts => ⌜r = true⌝) (onContinue := fun xs letMuts =>
+      ⌜xs.prefix = [] ∨ xs.suffix = []⌝)
 -/
 #guard_msgs (info) in
 theorem earlyReturnWithoutLetMut_suggest_invariant (l : List Int) : earlyReturnWithoutLetMut l := by
@@ -208,9 +206,8 @@ def notQuiteEarlyReturn (l : List Nat) : Option Nat := Id.run do
 
 /--
 info: Try this:
-  invariants
-    · ⇓⟨xs, letMuts⟩ =>
-      ⌜xs.prefix = [] ∧ letMuts = ⟨none, ()⟩ ∨ xs.suffix = [] ∧ letMuts.fst = l.getLast?⌝
+  [apply] invariants
+  · ⇓⟨xs, letMuts⟩ => ⌜xs.prefix = [] ∧ letMuts = ⟨none, ()⟩ ∨ xs.suffix = [] ∧ letMuts.fst = l.getLast?⌝
 -/
 #guard_msgs (info) in
 theorem notQuiteEarlyReturn_suggest_invariant (l : List Nat) : notQuiteEarlyReturn l = l.getLast? := by
@@ -229,8 +226,8 @@ def polySum [Monad m] (l : List Nat) : m Nat := do
 
 /--
 info: Try this:
-  invariants
-    · ⇓⟨xs, letMuts⟩ => ⌜xs.prefix = [] ∧ letMuts = ⟨0, 0⟩ ∨ xs.suffix = [] ∧ letMuts.fst = l.sum⌝
+  [apply] invariants
+  · ⇓⟨xs, letMuts⟩ => ⌜xs.prefix = [] ∧ letMuts = ⟨0, 0⟩ ∨ xs.suffix = [] ∧ letMuts.fst = l.sum⌝
 -/
 #guard_msgs (info) in
 theorem polySum_suggest_invariant [Monad m] [WPMonad m ps] (l : List Nat) : ⦃⌜True⌝⦄ @polySum m _ l ⦃⇓ r => ⌜r = l.sum⌝⦄ := by
@@ -247,11 +244,10 @@ def polyNodup [Monad m] (l : List Int) : m Bool := do
 
 /--
 info: Try this:
-  invariants
-    ·
-      Invariant.withEarlyReturn (onReturn := fun r letMuts => ⌜l.Nodup ∧ (r = true ↔ l.Nodup)⌝)
-        (onContinue := fun xs letMuts =>
-        ⌜xs.prefix = [] ∧ letMuts = seen✝ ∨ xs.suffix = [] ∧ l.Nodup⌝)
+  [apply] invariants
+  ·
+    Invariant.withEarlyReturn (onReturn := fun r letMuts => ⌜l.Nodup ∧ (r = true ↔ l.Nodup)⌝) (onContinue :=
+      fun xs letMuts => ⌜xs.prefix = [] ∧ letMuts = seen✝ ∨ xs.suffix = [] ∧ l.Nodup⌝)
 -/
 #guard_msgs (info) in
 theorem polyNodup_suggest_invariant [Monad m] [WPMonad m ps] (l : List Int) : ⦃⌜True⌝⦄ @polyNodup m _ l ⦃⇓r => ⌜r ↔ l.Nodup⌝⦄ := by
@@ -277,9 +273,8 @@ open Std.Do
 
 /--
 info: Try this:
-  invariants
-    · ⇓⟨xs, letMuts⟩ =>
-      ⌜xs.prefix = [] ∧ letMuts = ⟨n, x, 1⟩ ∨ xs.suffix = [] ∧ letMuts.2.snd = x ^ n⌝
+  [apply] invariants
+  · ⇓⟨xs, letMuts⟩ => ⌜xs.prefix = [] ∧ letMuts = ⟨n, x, 1⟩ ∨ xs.suffix = [] ∧ letMuts.2.snd = x ^ n⌝
 -/
 #guard_msgs (info) in
 theorem fast_expo_correct (x n : Nat) : fast_expo x n = x^n := by
@@ -321,11 +316,10 @@ theorem mkFresh_spec (c : Nat) :
 
 /--
 info: Try this:
-  invariants
-    ·
-      post⟨fun ⟨xs, letMuts⟩ =>
-        ⌜xs.prefix = [] ∧ letMuts = acc✝ ∨ xs.suffix = [] ∧ letMuts.toList.Nodup⌝, fun x => ⌜False⌝,
-        fun _msg state => ⌜state.counter = state.limit⌝⟩
+  [apply] invariants
+  ·
+    post⟨fun ⟨xs, letMuts⟩ => ⌜xs.prefix = [] ∧ letMuts = acc✝ ∨ xs.suffix = [] ∧ letMuts.toList.Nodup⌝, fun x =>
+      ⌜False⌝, fun _msg state => ⌜state.counter = state.limit⌝⟩
 -/
 #guard_msgs (info) in
 theorem mkFreshN_spec (n : Nat) :

tests/lean/run/partial_fixpoint_explicit.lean

@@ -52,7 +52,7 @@ partial_fixpoint monotonicity
 
 /--
 info: Try this:
-  exact fun x y a x_1 => a (x_1 + 1)
+  [apply] exact fun x y a x_1 => a (x_1 + 1)
 -/
 #guard_msgs in
 def nullary6 (x : Nat) : Option Unit := nullary6 (x + 1)

tests/lean/run/rewrites.lean

@@ -5,7 +5,7 @@ private axiom test_sorry : ∀ {α}, α
 
 /--
 info: Try this:
-  rw [@List.map_append]
+  [apply] rw [List.map_append]
   -- no goals
 -/
 #guard_msgs in
@@ -14,7 +14,7 @@ example (f : α → β) (L M : List α) : (L ++ M).map f = L.map f ++ M.map f :=
 
 /--
 info: Try this:
-  rw [Nat.one_mul]
+  [apply] rw [Nat.one_mul]
   -- no goals
 -/
 #guard_msgs in
@@ -100,7 +100,7 @@ example : zero = 0 := by
 -- Discharge side conditions from local hypotheses.
 /--
 info: Try this:
-  rw [h p]
+  [apply] rw [h p]
   -- no goals
 -/
 #guard_msgs in
@@ -110,7 +110,7 @@ example {P : Prop} (p : P) (h : P → 1 = 2) : 2 = 1 := by
 -- Use `solve_by_elim` to discharge side conditions.
 /--
 info: Try this:
-  rw [h (f p)]
+  [apply] rw [h (f p)]
   -- no goals
 -/
 #guard_msgs in
@@ -120,7 +120,7 @@ example {P Q : Prop} (p : P) (f : P → Q) (h : Q → 1 = 2) : 2 = 1 := by
 -- Rewrite in reverse, discharging side conditions from local hypotheses.
 /--
 info: Try this:
-  rw [← h₁ p]
+  [apply] rw [← h₁ p]
   -- Q a
 -/
 #guard_msgs in

tests/lean/run/show_term.lean

@@ -6,7 +6,7 @@ Authors: Kim Morrison
 
 /--
 info: Try this:
-  exact (n, 37)
+  [apply] exact (n, 37)
 -/
 #guard_msgs in example (n : Nat) : Nat × Nat := by
   show_term
@@ -16,7 +16,7 @@ info: Try this:
 
 /--
 info: Try this:
-  refine (?_, ?_)
+  [apply] refine (?_, ?_)
 -/
 #guard_msgs in example : Nat × Nat := by
   show_term constructor
@@ -24,7 +24,7 @@ info: Try this:
 
 /--
 info: Try this:
-  fun {X} => X
+  [apply] fun {X} => X
 -/
 #guard_msgs in example : {_a : Nat} → Nat :=
   show_term by

tests/lean/run/simpLoopProtection.lean

@@ -362,7 +362,7 @@ example : d > 0 := by simp? only [dc, ca, ac]; exact testSorry
 
 /--
 info: Try this:
-  simp only [dc, h, Nat.one_pos]
+  [apply] simp only [dc, h, Nat.one_pos]
 -/
 #guard_msgs in
 example (h : c = 1) : d > 0 := by simp? only [dc, h, ca, ac, Nat.one_pos]

tests/lean/run/simpTrace.lean

@@ -21,7 +21,7 @@ def x4 := 1
 
 /--
 info: Try this:
-  simp only [x1_eq_x2, x2_eq_x3, x3_eq_x4]
+  [apply] simp only [x1_eq_x2, x2_eq_x3, x3_eq_x4]
 -/
 #guard_msgs in
 example : x1 = x4 := by
@@ -33,7 +33,7 @@ example : x1 = x4 := by
 
 /--
 info: Try this:
-  simp only [x1_eq_x2, x2_eq_x3, x3_eq_x4]
+  [apply] simp only [x1_eq_x2, x2_eq_x3, x3_eq_x4]
 -/
 #guard_msgs in
 example : x1 * x1 = x4 * x4 := by
@@ -54,7 +54,7 @@ def test : Nat → Nat
 
 /--
 info: Try this:
-  simp only [test]
+  [apply] simp only [test]
 -/
 #guard_msgs in
 example : [test 3, test 2, test 4, test 5, test 0] = [4, 9, 16, 0, 3] := by
@@ -66,7 +66,7 @@ example : [test 3, test 2, test 4, test 5, test 0] = [4, 9, 16, 0, 3] := by
 
 /--
 info: Try this:
-  simp only [a]
+  [apply] simp only [a]
 -/
 #guard_msgs in
 example : let a := 5; a = 5 := by
@@ -79,7 +79,7 @@ example : let a := 5; a = 5 := by
 
 /--
 info: Try this:
-  simp only [h]
+  [apply] simp only [h]
 ---
 error: unsolved goals
 a b : Nat
@@ -108,7 +108,7 @@ simproc dontRewriteY2 (y2) := fun _ => do
 info: was run
 ---
 info: Try this:
-  simp only [rewriteY1]
+  [apply] simp only [rewriteY1]
 -/
 #guard_msgs in
 example : y1 = y2 := by
@@ -116,7 +116,7 @@ example : y1 = y2 := by
 
 /--
 info: Try this:
-  simp only [Nat.reduceAdd]
+  [apply] simp only [Nat.reduceAdd]
 -/
 #guard_msgs in
 example : 1 + 1 = 2 := by
@@ -135,8 +135,8 @@ theorem wait_this_is_rewritten_backwards_and_wow_it's_very_clear_and_obvious : z
 
 /--
 info: Try this:
-  simp only [very_long_lemma_oh_no_can_you_please_stop_we're_getting_to_the_limit,
-      ← wait_this_is_rewritten_backwards_and_wow_it's_very_clear_and_obvious]
+  [apply] simp only [very_long_lemma_oh_no_can_you_please_stop_we're_getting_to_the_limit,
+    ← wait_this_is_rewritten_backwards_and_wow_it's_very_clear_and_obvious]
 -/
 #guard_msgs in
 example : z1 = z3 := by

tests/lean/run/simp_arith_deprecated.lean

@@ -1,7 +1,7 @@
 /--
 info: Try these:
-  • simp +arith
-  • simp +arith +decide
+  [apply] simp +arith
+  [apply] simp +arith +decide
 ---
 error: `simp_arith` has been deprecated. It was a shorthand for `simp +arith +decide`, but most of the time, `+decide` was redundant since simprocs have been implemented.
 -/
@@ -11,8 +11,8 @@ example : x + 2 = 1 + 1 + x := by
 
 /--
 info: Try these:
-  • simp +arith [h, id] at h₂
-  • simp +arith +decide [h, id] at h₂
+  [apply] simp +arith [h, id] at h₂
+  [apply] simp +arith +decide [h, id] at h₂
 ---
 error: `simp_arith` has been deprecated. It was a shorthand for `simp +arith +decide`, but most of the time, `+decide` was redundant since simprocs have been implemented.
 -/
@@ -22,8 +22,8 @@ example (h : x = y) (h₂ : y + 2 = 1 + 1 + x) : True := by
 
 /--
 info: Try these:
-  • simp! +arith [h, id] at h₂
-  • simp! +arith +decide [h, id] at h₂
+  [apply] simp! +arith [h, id] at h₂
+  [apply] simp! +arith +decide [h, id] at h₂
 ---
 error: `simp_arith!` has been deprecated. It was a shorthand for `simp! +arith +decide`, but most of the time, `+decide` was redundant since simprocs have been implemented.
 -/
@@ -34,8 +34,8 @@ example (h : x = y) (h₂ : y + 2 = 1 + 1 + x) : True := by
 
 /--
 info: Try these:
-  • simp_all +arith
-  • simp_all +arith +decide
+  [apply] simp_all +arith
+  [apply] simp_all +arith +decide
 ---
 error: `simp_all_arith` has been deprecated. It was a shorthand for `simp_all +arith +decide`, but most of the time, `+decide` was redundant since simprocs have been implemented.
 -/
@@ -45,8 +45,8 @@ example (h : x = y) (h₂ : y + 2 = 1 + 1 + x) : True := by
 
 /--
 info: Try these:
-  • simp_all! +arith
-  • simp_all! +arith +decide
+  [apply] simp_all! +arith
+  [apply] simp_all! +arith +decide
 ---
 error: `simp_all_arith!` has been deprecated. It was a shorthand for `simp_all! +arith +decide`, but most of the time, `+decide` was redundant since simprocs have been implemented.
 -/

tests/lean/run/zetaDeltaTryThisIssue.lean

@@ -2,7 +2,7 @@ opaque f : Nat → Nat
 
 /--
 info: Try this:
-  simp only [h1, x]
+  [apply] simp only [h1, x]
 ---
 warning: declaration uses 'sorry'
 -/
@@ -16,7 +16,7 @@ example (a : Nat) : True := by
 
 /--
 info: Try this:
-  simp only [this, x]
+  [apply] simp only [this, x]
 ---
 warning: declaration uses 'sorry'
 -/

tests/lean/termination_by.lean.expected.out

@@ -14,4 +14,4 @@ termination_by.lean:62:2-62:23: error: incomplete set of termination hints:
 This function is mutually recursive with isOdd, which does not have a termination hint.
 The present clause is ignored.
 Try this:
-  termination_by x1 => x1
+  [apply] termination_by x1 => x1